<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>语义化标签的使用</title>
    <style>
        header {
            width: 100%;
            height: 100px;
            background-color: red;
        }
        nav {
            width: 100%;
            height: 30px;
            background-color: blue;
        }
        main {
            width: 100%;
            height: 500px;
            background-color: #ccc;
            flex-direction: row;
            display: flex;
        }
        main > article {
            width: 70%;
            height: 100%;
            background-color: purple;
            /* float: left; */
        }
        main > aside {
            width: 30%;
            height: 100%;
            background-color: pink;
            /* float: right; */
        }
        footer {
            width: 100%;
            height: 30px;
            background-color: yellow;
        }
    </style>
</head>
<body>
    <header>头部</header>
    <nav>导航</nav>
    <main>
        <article>左侧</article>
        <aside>右侧</aside>
    </main>
    <footer>底部</footer>
</body>
</html>